CNC Machining Alkali-Free Glass – Alkali-Free Glass (CTE 3.2 x 10^-6 /K, 350 nm – 2.0 um); CNC Machining to +/-0.01 mm positional. No minimum order; DFM review included with every RFQ.
Ask any process engineer what makes alkali-free glass difficult and the answer is specific: thin sheets below 0.3 mm demand carrier-supported handling through every step. Our cnc machining line is tooled around exactly that – 4-axis machining centers with diamond tooling and through-spindle coolant – holding +/-0.01 mm positional on parts from 0.5 – 50 mm thick.
Specification envelope
| Material | Alkali-Free Glass (AF32 / EAGLE-class display glass) |
|---|---|
| Thermal expansion (CTE) | 3.2 x 10^-6 /K |
| Service temperature | 600 C (Tg 717 C) |
| Transmission range | 350 nm – 2.0 um |
| Density | 2.43 g/cm3 |
| Knoop hardness | 590 kg/mm2 |
| Refractive index | 1.51 @ 587 nm |
| Stock thickness | 0.10 – 1.1 mm |
| Maximum blank size | 400 x 300 mm |
| Process | CNC Machining |
| Working tolerance | +/-0.01 mm positional |
| Minimum feature | 0.4 mm slot width |
| Surface finish | Ra 0.4 um ground, optional polish |
| Thickness window | 0.5 – 50 mm |
| Edge condition | chamfered 0.1 – 0.5 mm as standard |
| RFQ inputs | PDF/DXF/STEP drawing, quantity brackets, surface and edge spec |
Manufacturing capability
The core strength of CNC Machining is complex 3D geometry – pockets, steps, counterbores and compound edges in one setup. The honest limit: internal corners carry a minimum radius equal to the smallest practical tool, typically R0.5 mm. Both belong on the drawing before quoting, not after.
One material, many routes: on Alkali-Free Glass we also quote double-side polishing, lapping, grinding, etching, and multi-step drawings are the norm rather than the exception.
Design guidance
Before sending the RFQ, check these against your drawing:
- Material note: thin sheets below 0.3 mm demand carrier-supported handling through every step.
- Process boundary: internal corners carry a minimum radius equal to the smallest practical tool, typically R0.5 mm.
- Over-specification is the quiet budget killer: a 20/10 scratch-dig face costs roughly three times an 80/50 face, so grade each surface individually.
The full rules live in our tolerance design guide and holes and edges design guide.
Typical applications
cnc machining alkali-free glass shows up across oled packaging (cover lids, frit-seal frames, fill-port plates); industrial displays (touch covers, gauge windows, printed bezels); ccd inspection equipment (CCD cover plates, reference grids, stage glass). Background reading on the underlying material science: SCHOTT AF 32 eco.
Dimensions still moving? Configure this part live in the 3D builder below, or open the full custom glass machining 3D builder to start from a blank canvas.
Useful companion pages: alkali-free display glass, alkali-free glass wafers, CNC machining capability.
Buyer questions, answered
What tolerances are achievable on Alkali-Free Glass parts?
Ground features hold +/-0.01 mm and lapped thickness reaches +/-0.003 mm. Thin sheets below 0.3 mm demand carrier-supported handling through every step.
What thickness range do you stock for Alkali-Free Glass?
Standard stock spans 0.10 – 1.1 mm, with blanks up to 400 x 300 mm. Other formats are sourced per order.
How does Alkali-Free Glass behave under heat?
CTE is 3.2 x 10^-6 /K and continuous service reaches 600 C (Tg 717 C), which is what drives its use where no alkali ion migration into TFT or sensor layers matters.
What accuracy does cnc machining hold?
+/-0.01 mm positional with minimum features of 0.4 mm slot width. Internal corners carry a minimum radius equal to the smallest practical tool, typically R0.5 mm.
What equipment runs the cnc machining work?
4-axis machining centers with diamond tooling and through-spindle coolant.
Specifications on this page were last reviewed by our engineering team in July 2026.